Apparatus for determining pressure and temperature in a well



G. H. ENNIS Feb. 13, 1940.

APPARATUS FOR DETERMINING PRESSURE AND TEMPERATURE IN A WELL 2 Sheets-Sheet 1 Original Filed July 25, 1934 A 770R wax 2 Sheets-Sheet 2 [/v vzxv TOR GEORGE H f/v/v/s A rTOR/VEY.

G. H. ENNIS Original Filed July 25, 1934 APPARATUS FOR DETERMINING PRESSURE AND TEMPERATURE IN A WELL Feb. 13, 1940.

Patented Feb. 13, 1940 PATENT OFFICE APPARATUS FOR DETERMINING PRESSURE AND TEDIPERATURE IN A WELL George H. Ennis, Long Beach, Calif., asslgnor of one-half to Robert V. Funk, Long Beach, Cali Continuation of application Serial No. 736,892, July '25, 1934. This application January 21, 1936, Serial No. 60,143

v 1 a I ;3 Claims. (01. 73-445) My invention relates to the' oil producing industry andlrelates particularly to an apparatus by which temperaturesorpressures, or both, which exist within an oil well maybe correctly determined at the surface of the ground. It is well known in the oil producing industry that i such information is of great value in obtaining maximum oil production from the oil fields and in securing best emciency. I 1

It is an object of my invention to provide an apparatus which will, correctly determine. accurate temperatures or pressures, or both temperatures and pressures, which exist in a well.

.It is another object of my invention to provide an apparatus of the character pointed out heretofore in which any changes which occur in the condition of the transmitting means whereby the intelligence is transmitted to the surface of the ground may be determined, and in which the indication or reading is corrected in accordance therewith in order that a correct temperature or pressure, or temperature and pressure, reading may be obtained.

It is also an object of my invention to provide 35 an apparatus in which data obtained at the surface of the ground may be corrected in accordance with any changes which occur in the transmitting means in order that such changes may be compensated for in order that accurate data may 30 be obtained. Producing oil wells usually comprise a casing extending down into the oil producing zone, and

a tubing within the casing. To take a well of! production and shut oil the flow therefrom in or- 35 der to make a test of the temperature or pressure of the liquid in the well is a laborious, time conapparatus for measuring pressure and temperatureat various depths in a well which does not require that the well be taken off. production or that the tubing be removed from the well and whichpermits the measurements of such condi- 50 tions to be made within the casing and below the lower end of the tubing.

Further objects of my invention are to provide an apparatus of the class described which can be quickly and easily installed in and removed from an oil Well and which is inexpensive 'ported in any suitable manner upon the derrick in its manufacture, durable inits service, and accurate and dependable in its functions.

The foregoing objects and advantages will be made evident in the following description of the preferred embodiment of the apparatus of my 5 invention, which. may be better understood with reference to the accompanying drawings in which, I

Fig. l is a utility view illustrating an embodiment of the apparatus of my invention installed in an oil well;

Fig. 2 is a fragmentary sectional view of a portion of such embodiment;

Figs. 3 to 5, inclusive, are sectional views taken as indicated by the correspondingly numbered lines of Fig. 2;

Fig. 6 is a vertical sectional view-of another portionof the apparatus of my invention;

Fig-7 is a sectional view taken an indicated by the line 1-1 of Fig. 8: 1

Fig. 8 is a fragmentary view taken as indicated by the line 8-8 of Fig, 7; and

Fig. 9 is a diagrammatic view of the electric, circuit of the apparatus of my invention.

Referring to the drawings, which are for illustrative purposes only, the numeral ll indicates a casing extending from a derrick floor l2 down in an, oil well to the oil producing zone. Secured to the upper end of the casing II is ahead l2 supthreaded opening 15 is a fitting i6 having a cab tral opening therein and supporting a packing member I! thereabove. The packing member I! has a central opening and suitable packing, not

shown, so that a cable I8 may be extended through the packing member I! and the fitting I5 into the well in such a manner that the cable l8 may be moved upwardly or downwardly while maintaining a fluid-tight engagement with the packing member l1.

- Secured to the head, is an on tubing is which extends downwardly within the casing H.

, Adapted to be loweredthrough the tubing I! on the cable I 8 is a cylindrical body 20 of a considerably lesser external diameter than the internal diameter of the tubing ll. At the lower m end of the cylindrical body is a portion .2I of reduced diameter which is provided with external threads 22 for threaded engagement with a telescoping member 23 extending upwardly around the reduced portion 2| The lower end of the telescoping member 23 is threaded to an upper sleeve member 24 which is of substantially the same external diameter as the cylindrical body and has a reduced portion 25. Connecting the reduced portion 25 of the upper sleeve member 24 to a lower sleeve member 26 of substantially the same diameter as the reduced portion 25 are four engagers 21.

As is well illustrated in Fig. l, the engagers 21 are curved outwardly and, being formed of resilient material, they are urged into frictional engagement with the interior of the tubing l9 or the casing H by a compression spring 21a. The upper end of the compression spring 21a urges the lower sleeve member 25 upwardly, thus tending to move the engagers 21 outwardly, the lower end of the spring 21a abutting against a cap 23 threaded on the lower end of a rod 29 which extends through the lower sleeve member 25 and is secured to the upper sleeve member 24. Contactors 30 in the form of knife edges of tungsten carbide or stellite, or any suitable conductor having good wear-resisting qualities, are secured to the outer face of the engagers 21 substantially midway between their ends so that the contactors 30 may cut through any foreign material on the inner surface of the tubing I! or the casing ii to make a good electrical contact for the engagers 21.

As is well illustrate in Figs. 2 and 4, the upper end of the telescoping member 23 engages the annular shoulder separating the reduced portion 2| from the remainder of the cylindrical body 20. The telescoping member 23 is provided with inwardly projecting longitudinal fins 3| engaging the reduced portion 2| and defining between the telescoping member 23 and the reduced portion 2| longitudinal passages 32. Each of the longitudinal passages 32 communicates at its upper end with the exterior of the telescoping member 23 through radial passages 53 and communicates at its lower end with the interior of the cylindrical body 25 through radial passages 34.111 the reduced portion 2|.

Resting upon an annular shoulder separating the lower externally threaded end of telescoping member 23 from the remainder of the interior of the member 23 are downwardly extending radial projections 35 of a cap 36 which has a central upwardly extending, externally threaded hub 31. Secured to the projection 31 is a locking member 38 having an inwardly extending flange 39 delining a central passage o! the same diameter as a passage 38:: in the projection 31. The locking member 38 includes an upwardlyextending projection 4| defining an outer and inner annular shoulders 42 and 43, respectively, and is provided with a plurality of vertical bores 44 for the reception of screws 45 which extend through the locking member 38 and are threadedly received in a ring 45 above the locking member 35. The ring 45 has an external diameter slightly less than the external diameter of the projection 4| of the locking means 38 and an inner diameter slightly greater than theinner diameter of the projection 4|.

Secured within the cylindrical body 25 as by a force fitting or in any other suitable manner, is an outer stationary sleeve 41 with its lower end resting upon the outer annular shoulder 42 of the locking member 38, and with its upper end approximately on the level of the radial passages 32 of the cylindrical body 25. Resting on the inner annular shoulder 43 of the locking member 38 and secured in any suitable manner, as by welding to the ring 46, is an inner stationary sleeve 48 of approximately the same length as the outer stationary sleeve 41. The inner stationary sleeve 48 has an inner diameter substantially equal to the diameter of the passages 38a and 40, except for a portion 49 at the upper end which is of an enlarged diameter for the reception of a packing gland 50. The gland 5D surrounds, in fluid-tight relationship, a plunger 5| slidably disposed within the inner stationary sleeve 48. Secured to the lower end of the plunger 5| there is a plunger head 52 of rubber, leather or the like, and positioned so as to engage the upper end 01 the plunger 5| there is a movable cylinder 53. The movable cylinder 53 includes an imperforate bottom 54 and is open at its upper end. Secured to the lower surface of the bottom 54 is the upper end of a tension spring 55, the lower end of which is secured in any suitable manner, as by welding, to the upper face of the ring 45.

A plurality'of electrical contacts 55 is secured to the upper end of the movable cylinder 53. As illustrated in Fig. 3, the movable contacts 56 are eight in number and are preferably formed by upwardly and inwardly extending resilient fingers adapted for resiliently engaging the surface of a resistance supporting cylinder 51. The cylinder 51, which is formed of material 01' good insulating quality, has spirally wound thereon a resistance wire 58, the outer diameter of the cylinder 51 and the wire wound thereon being less than the inner diameter of the cylinder 55, so that the cylinder 53 may move to surround the resistance-supporting cylinder 51 which is held centrally of the cylindrical body 2|) and stationary therein as by arms 59 extending outwardly from the upper end of the cylinder 51 into engagement with the cylindrical body 20.

The resistance wire 58 is electrically connected to a conductor which extends between the arms 59 and is insulated relative thereto. The conductor 60 extends upwardly, as illustrated in Fig. 6, through a lower partition wall 5| and an upper partition wall 62, and is electrically connected to a brush 53.

Supported upon the lower partition 5| and extending upwardly therefrom is a container 54 having a lower reservoir 55 and an upper throat 66 of smaller diameter than the reservoir 55. Disposed within the container 64 is a resistance wire 51, the lower end oi which is electrically connected to the lower partition 5| which in turn is electrically connected to the cylindrical body 20. That portion of the resistance wire 51 within the throat B5 is coiled for a purpose which will be later described, and the upper end oi the resistance wire 61 is electrically connected to a conductor 58 which extends through the upper partition wall 62 and is electrically connected to a brush 55. The reservoir 55 of the container 54 is filled with a conductive liquid, such as mercury, so that the level of liquid is within the throat 55, as indicated by the numeral 15 of Fig. 6.

As illustrated in Fig. 7, the brush 63 is mounted upon a bracket 1| which is connected by an insulator 12 to the inner wall of the cylindrical body 20 and is adapted for continuous engagement with an outer ring 13 mounted in a primary disc 14. The primary disc 14 is non-rotatably secured to one end of a shaft 15, the other end of which is rotatably supported in a journal member 15 attached to the inner wall of the cylindrical body 20. The primary disc 14 is secured to a closed receptacle 11 which is substantially triangular in vertical cross-section. To the other side of the receptacle 'II there is secured a secondary disc I8 which is non-rotatably attached to a shaft I9 rotatably supported in a journal member 80 secured to the inner wall of the cylindrical body 20 diametrically opposite to the journal member I6, so that the shafts I9 and I5 are in axial alignment.

Rotatably mounted upon the shaft I5 is a housing 8I on which is provided a pinion 82. As is best illustrated in Fig. 8, the housing 8| has a central opening 83 of a diameter sufficient to permit the housing 8| to rotate freely on the shaft I5. Formed in the housing BI and communicating with the central opening 83 is a plurality of recesses 84, each of which has one wall 85 curved eccentric to the center of the opening 83 and one wall 86 radial of the opening 83 and intersecting the wall 85; Disposed within each of the recesses 84 is a ball 81, which balls are urged toward the narrow parts of the recesses 84 by springs 88. This forms a clutch arrangement of a well-known type, which enables the shaft "I5 to be rotated only in a clockwise direction.

In meshing relationship with the pinion 82 is a rack 89 having an arm 90 extending upwardly therefrom, and slidably supported by a bracket 9| secured to the inner wall of the cylindrical body 20, so that the rack 89 is held in meshing relationshipwith the pinion 82 and is vertically movable relative thereto.

The primary disc I4 is formed of a non-conductive material into the outer face of which the outer ring I3, is sunk. Electrically connected to the outer ring I3, which is formed of a conductive material, is a contact 92 which extends inwardly from the primary disc- I4 and into the closed receptacle IT. as illustrated in Figp'l. The primary disc I4 is also provided with an inner concentric annular ring 93 likewise formed of conductive material and set into the outer face of the primary disc I4. This inner ring 93 is engaged by a brush 94 mounted upon an arm 95 which is electrically connected to the inner wall of the cylindrical body 20, so that the inner ring 93 is grounded, and is therefore in electrical contact with the well casing which forms a part of the electrical circuit. Electrically connected to the inner ring 93 and extending inwardly therefrom, is a contact 96. As illustrated in Fig. 7, the contact 96 extends into the closed receptacle II and is spaced from the contact 92 approximately The brush 69, previously described, is in constant electrical contact with an outer annular ring 91 of conductive material set into the outer face of the secondary disc 18, which disc is formed of a non-conductive substance. The outer ring 91 is electrically connected to a contact 98 which extends into the closed receptacle I1 and is spaced approximately 120 from both the contact 92 and the contact 96. The brush 69, like the brush 63, is mounted upon a bracket 99 which is secured to the cylindrical body 20 and insulated therefrom by insulation I00.

Secured in a similar manner to the cylindrical body 20 by an insulator MI is a bracket I02 supporting a brush I03 which is in constant electrical connection with an inner ring I04 of conductive material set into the outer face of the secondary disc I8 concentric with the outer ring 91. The inner ring I04 is provided with one contact I05 which exmnds through the secondary disc I8 into the closed receptacle 11 adjacent the contact 98. The inner ring I04 is also conelectrical contact.

nected to another contact I06 which extends through the secondary disc I8 and into the closed receptacle 1! adjacent the contact 98. A third contact I01 is provided on the inner ring I04 and extends into the closed receptacle 11 adjacent the contact. 92. The closed receptacle I7 contains a body I08 of a conductive liquid, such as mercury, of a suflicient quantity so that when any one of the apexes of the triangular receptacle TI is lowermost, the body of conductive liquid will electrically connect the contacts 98 and I06, or the contacts 92 and I01, or the contacts 96 and I05.

Connected to the bracket I02 and extending upwardly therefrom is a conductor I09 which is electrically connected at the surface of the ground to a brush IIO of a circuit interrupter III. The circuit interrupter I.II includes a disc II2 of non-conductive material to which there is secured three segments H3, H4 and H5 of conductive material. As illustrated in Fig. 9, the segment I I3 extends through approximately 270, while the segments H4 and H5 extend through approximately 30.

- Also mounted on the disc H2 is an inner ring II6 of conductive material which is electrically connected by a brush III to one terminal of a current indicating device II8, the other terminal of the device being grounded by a conductor H9 to the casing II with which the body 20 is in Connecting each of the seg ments II3 to H5 to the inner ring H8 is a resistance I20. Each segment is also electrically connected to an engager I2I adapted for electrical contact with one of the resistances I 20 so that the electrical resistance between each of the segments II3 to H5 and the inner ring II6 may be varied. The purpose of providing the rheostats comprising the parts I20 and I2I is to provide suitable resistance in the circuit at different periods so that the pointer or indicator I28 of the indicating device II8 will indicate on the portions I26, I21, and I28 of the indicating means II8 when the switch, including the receptacle TI, is in its three positions corresponding to the contacts II3 to H5 inclusive which may be in engagement with the brush contact IIO.

The method of adjusting the rheostats will. be pointed out when a description of the apparatus and the method of my invention is described.

A solenoid I22 is disposed within the cylindrical body 20 above the discs 14 and I8, its winding being electrically connected to the conductor I09 and to the cylindrical body 20. The movable core of the solenoid I22 is attached to the rod 90 formed on the rack 89.

Connected to the indicating device II8 is a source of energy which is represented in the form of a battery I23. In actual practice this source of energy may be a constant voltage generator or equivalent. I

From an inspection of Fig. 9 it will be seen that the apparatus of my invention includes an electric circuit which extends from a point at the surface of the ground to a point in the well where the temperature or pressureinformation is desired. This electric circuit includes the electrical the form of the indicating means H8 which is operated in conjunction with the interrupter I I I. It should be understood, however, that other types of indicating means which would automatically indicate the three separate indications without the necessity of the interrupter III may be employed, such indicating devices being well known in the electrical indicating industry at the time of filing this application.

Adapted to be connected to the electrical circuit at intervals is the temperature responsive means and the pressure responsive means. In conjunction with these general parts is the means whereby the temperature responsive means may be connected in the electrical circuit or the pressure responsive means may be connected in the electrical circuit, or whereby both of these apparatus may be disconnected from the electrical circuit and the electrical circuit closed at the point in the well where the temperature and pressure responsive means are located in order that the indicating means II8 will indicate only the resistance of the electrical circuit or the condition of the electrical circuit which, as pointed out heretofore, may vary in accordance with temperatures, contacts, and conditions of the well casing. It will be noted that the electrical circuit constitutes the means of my invention whereby the effect of temperature on the temperature respon-, sive device or pressure on the pressure responsive device may be transmitted to the surface of the ground and be indicated on the indicating means H8.

In using the apparatus which I have shown it is first desirable to calibrate the indicating device H8, and this may be done as follows. The apparatus which is to be lowered into the well is first placed in a chamber wherein a known pressure may be built up. The parts of the apparatus at this time are adjusted so that the pressure responsive device is connected to the conductor in the cable I8 and the device grounded on the other side of the circuit to take the place of that portion of the circuit constituting the casing and conductor II! when the device is in operation in the well. The associated rheostats comprising the parts I and I2! are then adjusted so that the pointer I properly indicates the pressure on the dial of the indicating device H8. The resistance of the circuit is then determined and of course the voltage of the current source is also known. An indicating device may record amperes or may be calibrated to indicate pounds pressure per square inch. However, with the three factors; namely, voltage, amperage, and resistance known, it is possible to form an equation whereby a change in the indication of the indicating device or in the resistance of the circuit may be used to determine correctly the pressure in the well.

The apparatus may then be subjected to a known temperature with the apparatus connected so that the temperature responsive means is connected to the electrical circuit, and the same type of calibration may be made. The apparatus is now ready to be lowered into the well and this is conveniently done since the cable including the conductor I09 is wound on the drum I24.

Before the device is lowered, clean oil of substantially the same characteristics as the oil in the well is poured through the openings 33 filling the passages 32 and 34, and the cylindrical passages 380. and 40. During the descent of the apparatus, the contactors of the engagers 21 engage the inner wall of the tubing I8, but the resistance to downward travel of the apparatus resulting from this engagement is made insuiiicient by proper adjustment of the spring 21a to prevent the downward gravitational movement of the device. It should be particularly noted that the mechanism is such that the cylindrical body 20 can be of a sufliciently small diameter to pass through tubing I8 having any inner diameter commercially used. When the cylindrical body 20 passes below the lower end of the tubing I8 the engagers 21 expand in response to the compression of the spring 21a so that the contactors 30 engage the inner wall of the casing II, Inasmuch as the contactors 30 are in the form of knife edges and are made of very hard material, an electrical contact is secured with the casing II even though the casing may be coated with rust or dirt. When the device has reached that level in the well at which it is desired to measure or determine the temperature and pressure of the liquid, which 'depth is ascertained by the length of the cable I8 which has been unreeled, the unreeling operation is terminated. The pressure on the liquid in the well at this level is communicated through the clean oil in the passages 32, 34, 38a and 40, and is exerted upon the plunger head 52. Thus the plunger 5I is urged upwardly with a force which is a function of the pressure of the liquid in the well. The upward movement of the plunger 5| and movable cylinder 53 attached thereto is resisted by the tension spring 55 so that the upward movement of the.

movable cylinder 53 is a function of the pressure on the liquid to be measured. As the movable cylinder 53 moves upwardly, the contactors 56 pass over the windings of the resistance wire 58 upon the resistance supporting cylinder 51, thus cutting out of the electrical circuit some resistance. The value of the resistance eliminated by the upward movement of the contactors 56 being a function of the pressure on the liquid to be measured, it is evident that the recording device II8, having an indicator I25 movable in response to current variations, will be moved over the scale I26 a distance which is a function of this pressure. The scale I26 is graduated in pounds per square inch, so that the indicator I25 indicates directly the pressure upon the liquid at the desired level in the well.

The electrical circuit enabling this indication to be secured is illustrated in Fig. 9 of the drawings, which shows one side of the source of potential as being connected through the indicating device II8 by a conductor H3 to a ground. The other side of the source of potential is connected through the indicating device II8 to the brush ill of the circuit interrupter III. The \brush H1 is connected through the inner ring H8; the resistance I20 and contactor I2I, the segment H3 and brush H0, to the solenoid I 22 and to the cylindrical body 20. The passage of current through the winding of the solenoid I22 lifts the core upwardly, which moves the rod 90 and rack 88 to its uppermost position. The upward movement of the rack 88 moves the housing member ill in a counter-clockwise direction, as viewed in Fig. 8, so that the balls 81 are in contact with the walls 86, and this rotation of the housing 8| results in no move ment of the shaft I5.

The circuit from the brush IIO includes the conductor I09, brush I03, contact I06, contact I01, body of mercury I08, contact 82, outer ring '13, brush 63, conductor 60, resistance wire 58,

cylindrical body 20, engagers 27, and contactors 30 which ground the circuit to the casing II. It should be apparent that the upward movement of the movable cylinder 53 by diminishing the length of the resistance wire 58 in the circuit varies the current therein to give a sensible indication through the indicator I25 and the scale I26.

When the indication of the pressure on the liquid in the well has been noted, the circuit interrupter III is actuated by the rotation of the disc H2 in a clockwise direction, as indicated in Fig. 9, so that the brush IIO moves out of contact with the segment H3 and after an interval of time into contact with the segment H5. During the time that the brush H0 is in contact with no segment, the circuit through the solenoid I22 is interrupted, permitting the solenoid core and rod 90 and rack 89 to descend to its lowermost position by gravity. During the downward movement of the rack 89 the pinion 82 is rotated in a clockwise direction, as illustrated by the arrow 88a of Fig. 8. This rotation of the pinion 82 and housing 8I causes the balls 87 to be compressed by the curved walls and the shaft 15, thus effecting the rotation of the shaft 15 in a direction indicated by the arrow 88a. The rack 89 is of such a length that its descent causes the rotation of the shaft I5 through one-third of a revolution. This rotation of the shaft "I5 isaccomplished by a corresponding rotation of the primary and secondary discs 74 and I8 and the closed receptacle ll. It should be particularly noted that during the period of time that this movement of the discs I4 and i8 and receptacle TI is occurring, and the electrical connection between the contacts 92 and I0] is being disrupted, and the electrical connection between the contacts 96 and I05 is being established, the-circuit through these contacts is open so that there is no liability of dangerous arcs being formed.

Asthe disc II2 of the circuit interrupter I II continues to revolve, the brush H0 is brought into electrical contact with the segment H5, at which time the solenoid I22 is again energized, lifting the rod .90 and rack 89, which, as previously explained, is accomplished by no rotation of the shaft "I5. The electrical connection of the-brush IIO with the segment II5 establishes the circuit through the conductor I09, brush I03, inner ring I04, contact. I08, body of mercury I08, contact 98 (the receptacle having been rotated so that that apex in which the contacts I06 and 9B are situated is now lowermost), the outer ring 91, brush 69, conductor 68, and resistance wire 61 which is connected through the cylindrical body 20 to the ground. The partition wall 62 being in fluid-tight engagement with the conductors 68 and 60, and. partition wall 6| being in fluid-tight engagement with the conductor 60, the mercury in the container 64 is at approximately atmospheric pressure. By radiation, the temperature of the mercury, at short .while after its submersion in the liquid in the well, becomes the same as the temperature of such liquid, and expands or contracts in response to such temperature. The reservoir 65, being of greater dimensions than the throat 65 of the container 64, the expansion or contraction of the body of mercury causes themercury to ascend or descend in the throat 66 to a very appreciable extent. As the mercury ascends or descends in the throat 66, the effective resistance of the resistance wire 6'! is decreased or increased so that a visible indication of this resistance, and hence the temperature of the liquid in the well, is indicated upon the indicating device H0. The contactors I2I having been adjusted relative to the re- 5 sistances I20 of the segments H5 and II3, so that the indicator I25 of the indicating device I I8 moves over the scale I21 upon the indicating device to indicate temperature, it should be apparent that if the scale 121 has been graduated empirically, the indicator I25 will indicate thereon correctly, in degrees, the temperature of the liquid in the well.

It will be understood, however, that the recordings, indications, or determinations of the indicating device II8 will bev correct only if the voltage of the source of energy I23 and the resistance in the electrical circuit have not varied. Since the source of electrical energy is a con stant potential source, this factorfneed not be taken into consideration. However, in view of the fact that any temperature change in the well affects the resistance of the electrical circuit, and in view of the fact that changes in contact with the casing or changes in the easing itself will affect the resistance of the electrical circuit, it is necessary to periodically check the resistance of. the circuit and this is done after each temperature and pressure reading has been taken.

When the temperature of the liquid has been recorded, the disc II2 of the circuit interrupter III is rotated until the brush IIO moves out of contact with the segment II5. During the interval of time that the brush H0 is in contact with neither of the segments I I3 to I I5, the solenoid I22 is de-energized, permitting the arm and rack 89 to descend, thus rotating the shaft I5, primary disc -I4, secondary disc 13 and recep tacle 1! through approximately 120, as previously described; so that the body of mercury I08 in the receptacle I'l disconnects the contacts I06 and 98 and connects the contacts I05 and 98 while no current is flowing through the circuit. When the circuit interrupter has moved so that the brush I I 0 is in contact with the segment III, the solenoid I22 is again energized, lifting the rack 89, which causes no movement of the shaft I5. The engagement of the brush H0 with the segment II 4 completes the circuit through the conductor I09, brush I03, inner ring I04, contact I05, body of mercury I08, contact 36, inner ring 93, brush 94 and conductor to the cylindrical body 20, and thus through the contactors 30 -to ground. 55

It will be seen that when the parts are in the position just described the temperature responsive means and the pressure responsive means are wholly disconnected from the electrical circuit and that the electrical circuit is completed or shunted at its lowermost point in the well. The indicating device H8 at this time will indicate or measure only the electrical resistance in the electrical circuit itself. It will be seen, therefore, that the exact resistance in the electrical circuit may be determined and that any changes in resistance in the electrical circuit will be indicated. By proper adjustment of the rheostat associated with the segment I the current in the circuit just described is made of such a value that the indicator I25 of the indicating device indicates the value of the current in this circuit upon the scale I28 which is distinct from the scales I26 and I2! on the indicating device.

With the data obtained on the operation of the 7 apparatus it is now possible to make any necessary corrections in the temperature or pressure indications in accordance with the conditions of the electrical circuit; that is, in accordance with the resistance or change in resistance which occurs during the operation of the apparatus or the performance of the process. For example, with the formula: volts divided by resistance equals amperage, and with the apparatus calibrated as explained heretofore the change in the resistance or any change in the amperage or the indication on the indicating means H8 may be employed to determine exactly what the pressure or the temperature within the well is. It will be seen that without the prior calibration to determine the relationship between the factors in the formula referred to and the temperature or pressure responsive means, or without the-information as to the changes in resistance in the electrical circuit, accurate data or information cannot be obtained.

While the circuit interrupted iii may be manually operated if desired, it may be mechanically actuated in any suitable manner, as by connecting the disc H2 to the shaft of the hour hand of aclock, so that one complete revolution of the disc 2 is accomplished each hour. Likewise, a recording device which includes means for continuously and permanently recording the values indicated by the indicator I25 may be substituted for the indicating device H8 illustrated in the drawings.

Inasmuch as the cylindrical body 20 of my invention may be made of very small external dimeter, and inasmuch as the engagers 2! permit the passage of the apparatus out of and into the lower end of the tubing i8, it is apparent that I have by my invention provided an apparatus of the class described which can be employed for its intended purpose while the well is on production without removing the tubing, and with any size of tubing commercially employed, and that such apparatus may be employed for its intended purpose below the lower end of the tubing and within the casing.

While that embodiment of my invention hereinbefore illustrated and described is fully capable of performing the objects and providing the advantages primarly stated, there are various other embodiments of my invention likewise capable of performing these objects and providing these advantages, and I therefore wish my invention to be understood as not restricted to the specific em= bodiment hereinbefore set forth.

The indicating means I I8 is typical of a measuring means which may be employed in the practice of my invention. In place of using a meter as illustrated one which makes a permanent record or graph may be employed. Likewise, either an ammeter, voltmeter, or other electricalresponsive mechanism may be employed. The term indicating means" or the 'step of indicating" as employed in the claims is to be broadly construed to cover any indicating or measuring means whereby the electrical values in the circuit may be measured and the data thus obtained employed for determining the temperature and pressure or other phenomena in the well.

This application is a continuation of my application for Method and apparatus for measuring pressure and temperature at various depths in a bore hole, Serial No. 736,892, filed July 25, 1934.

I claim as my-invention:

1. In an apparatus for determining, at the surface of the ground, phenomena which exist in a bore hole, the combination of: an electric circuit, a part of which extends into said bore hole; circuit breaking means operable to break said circuit; indicating means in said circuit; and apparatus adapted to be lowered into said bore hole to depths where said determination is to be made, said apparatus including pressure responsive means, temperature responsive means,.solenoid means connected in said circuit and being deenergized when said circuit is opened, and switch means operated by said solenoid, and operable upon successive cleenergization of said solenoid, for first connecting said pressure re-.

sponsive means to said circuit, and then said temperature responsive means to said circuit.

2. In anapparatus for determining, at the surface of the ground, phenomena which exist in a bore hole, the combination of: an electric'circuit, a part of which extends into said bore hole; circuit breaking means operable to break said circuit; indicating means in said circuit; and apparatus adapted to be lowered into said bore hole to depths where said determination is to be made, said apparatus including pressure responsive means'temperature responsive means, and switch means actuated by the successive opening and closing of said circuit, for first connecting said 'pressure responsive means to said circuit, and

then said temperature responsive means to said circuit, and also for closing said circuit at its lower end with said pressure and temperature re-- sponsive means disconnected from said circuit.

3. In an apparatus for determining, at the surface of the ground, phenomena which exist in a bore hole, in which a casing has been installed,

, the combination of: an electrical conductor conand switch means operable to include said phenomena responsive means in said circuit, or to close said circuit with said phenomena responsive means excluded therefrom, so that said indicating 'means may indicate the effect of said phenomena responsive means, or the conditionof said circuit.

' GEORGE H. ENNIS.

CERTIFICATE OF CORRECTION. Patent No. 2,190,260. ebruary 15, 19L1O.

GEORGE H. ENNIS.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page h, first column, line 52, for the word "record" read indicate; and that the' said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this znd dey of April; A. D. 19110.

(Seal) H nry Van Arsdale,

Acting Commissioner of Patents.

CERTIFICATE OF CORRECTION Patent No. 2,190,260. ebruary 15, 191 0.

GEORGE H. ENNIS.

It is hereby certified that erroreppears in the printed speeification of the above numbered patent requiring correctionas follows: Page 11,, first column, line 52, for the were "recoid" read indicateyand that the said Letters Patent should be read with this eorrection therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this Zmiday of April; A. D. 19110.

(Se 1) H nry Van Arsdale;

a 1 Acting Commissioner of Patents. 

